Ripper tooth



Aug. 31, 1965 J. EASTWOOD 111 3,203,488

RIPPER TOOTH Filed Sept. '1, 1962 s Sheets-Sheet 1 JOSEPH EASTWOOD IIIINVENTOR.

BY fliZAyw w ATTORNEYS Aug. 31, 1965 J. EASTWOOD m RIPPER TOOTH 3Sheets-Sheet 2 Filed Sept. 7, 1962 JOSEPH EASTWOOD III INVENTOR.

ATTORNEYS 31, 1965 J. EASTWOOD in 3,203,488

RIPPER TOOTH Filed Sept. 7, 1962 5 Sheets-Sheet 3 FIG. 5

FIG.7

FIG. 4

FIG.6

JOSEPH EASTWOOD III INVENTOR BY @AWMW ATTORNEYS United States Patents.

3,293,488 *RlPPER TO'OTI-I Joseph Eastwood III, Hayward, Calif.,assignor to Pacific States Steel Corporation, Union City, Calif, acorporation of California Filed Sept. 7, 1962, Ser. -No. 222,012 1'Claim. (Cl. 172-713) This invention relates to ripper tooth assembliesand more particularly to such assemblies including a mounting shank anda replaceable ripper tooth.

Ripping teeth have been used in the past to scarify earth structuressuch as rock and the like, by dragging the tooth below the surface ofthe earth with heavy machinery. Since the teeth are used on granite andother rock, it is apparent that they are subjected to extreme wear andmust, from time to time, be replaced. At the same time the teeth must bestrong enough to withstand the extreme digging action to which they areput.

Since the teeth must be replaceable, various means have been devised forsecuring individual teeth onto the shank. The teeth usually have arelatively fiat nose portion to assist in the digging action. Thus theymust be aflixed to the shank such that they maintain a definiteorientation.

In the prior art the teeth are usually made with a plug portion havingone or more flat or flattened sides which cooperate with a similarlyshaped socket in the shank to prevent twisting. Although flat orflattened plugs and sockets clearly prevent twisting, manufacturingproblems are presented. In order for the tooth to transfer to the shankthe various vertical and horizontal thrusts encountered during diggingoperations, the tooth must fit relatively well within the shank. Whileit is well known that forgings provide considerably greater strengththan cast materials, the dimensional tolerance of a flattened plug issubstantially less when forged than when cast. Consequently, if aflattened plug and socket arrangement were employed to connect the toothto the shank, it is almost imperative that the tooth be cast. Thesemachining operations are extremely expensive compared to the cost of thetooth itself and consequently forged teeth have not been commerciallyexploited to any great extent.

In view of the above, it is a general object of the present invention toprovide an improved tooth for earth working devices.

It is a more particular object of this invention to provide an improvedtooth for earth working devices which is readily replaceable and furtherwhich may be conveniently forged.

It is still another object of this invention to provide a tooth of theaforementioned character wherein a relatively tight fit exists betweenthe tooth and the mating shank section.

These and other objects and features of the invention will become moreclearly apparent upon a review of the following description inconjunction with the accompanying drawing, in which:

FIGURE 1 is an elevational view showing a digger tooth in accordancewith the invention, as found in normal use;

FIGURE 2 is an enlarged perspective and exploded view of the diggertooth and vertical shank as shown in FIGURE 1;

FIGURE 3 is a further enlarged detailed side elevational view of thetooth and shank shown in FIGURE 2;

FIGURE 4 is an enlarged top plan view of the tooth shown in FIGURES 2and 3;

FIGURE 5 is an end view of the tooth shown in FIG- URE 4;

3,203,488 Patented Aug. 31, 1965 FIGURE 6 is a side elevational view ofthe tooth shown in FIGURE 4;

FIGURE 7 is a sectional view taken along the line 7-7 of FIGURE 6; andFIGURE 8 is a side elevational view similar to that of FIGURE 3 butshowing a wear boot in addition thereto.

Referring to FIGURE 1 there is shown a ripper tooth assembly 11including a vertical shank 13 and a ripper tooth 15. The vertical shankof the assembly is shown connected as at 17 to a first tractor-likevehicle 19. A second tractor-like vehicle 21 is shown connected to thefirst with a tow bar 23 while a third vehicle 25 is shown behind thefirst whereby it is in a pushing relationship with respect to theassembly 11.

As the various vehicles are traveled along the surface 27 of the groundwhich may be rock or the like, the digger tooth 15 is forced through theearth itself leaving a cut 29. In practice the digger tooth 15 mayextend several feet below the surface of the earth and frequently itspath through the earth is assisted by periodic bumping from the rearwardvehicle 25 rather than a continuous push. Thus, it is apparent that thetooth 15, as well as the vertical shank 13, are subjected to extremestresses such that the tooth 15 itself must be constructed ofparticularly strong material.

As can be seen in FIGURE 2 and also in FIGURE 3, the shank 13 includes asocket member 31 secured at the lower end thereof by a weld 32 or thelike. The forward face 33 of the socket member includes generallyparallel shoulders 35 and 37 and a frusto-conically shaped socket 39. Abore 41, coaxial with the frustoconical socket 39, extends through theshank 13 land the socket member 31.

The ripper tooth itself, as can be better seen in FIG- URES 4-7,includes a digging portion formed by side walls 43 and 45 joinedtogether by a web 47 which terminates in a forward edge 49. The rear ofthe web 47 expands as at 51 to provide, in conjunction with the rearportions of the side Walls 43 and 45, a flange having relativelyparallel surfaces 53 and 55.

Rearward of the surfaces 53 and 55 is a frusto-conical shaped plug 57corresponding in shape and size with the frusto-conical socket 39. Therear of the plug 57 is tapped as at 59 to receive a threaded shaft 61(FIG. 3). The threaded shaft 61 extends through the bore 41 and, inconjunction with the nut 63 and washer 65, serves to retain the plug 57tightly in the socket 39. The parallel faces 53 and 55 cooperate withthe shoulders 35 and 37 whereby twisting of the tooth within the socketis prevented.

In the tooth shown, it is apparent that side thrust as well as thevertical thrust on the tooth 15 are transferred to the shank 13 throughthe medium of the frusto-conical plug and socket. It is likewiseapparent then that the plug 57 must fit securely within the socket 39such that these thrusts will not cause vibration or excessive shock,against the shank itself. Twisting movement of the tooth, on the otherhand, is prevented by means of the shoulders 35 and 37 in cooperationwith the parallel edges 53 and 55.

Since the portions of the tooth as well as the socket which require themost accurate fit are merely conical type surfaces, it is apparent thatforging is an economic and feasible method of manufacture, even if somereaming is required. Consequently, a high strength replaceable tooth isprovided. Since the shoulders 35 and 37 as well as the generallyparallel surfaces 53 and 55 merely prevent twisting movement on thetooth, it is clear that a high degree of accuracy is not required onthese surfaces. The manufacturing tolerances of normal forgingoperations are entirely suitable with no requirement of machining.

Referring to FIGURE 8, a similar ripper tooth as sembly is shown withthe exception that a wear boot 67 is provided in order to preventexcessive wear of the socket member 31. The wear boot 67 may be fittedover the socket member 31 and welded as at 69 to the shank 13.

I claim:

A ripper tooth assembly comprising a shank, a socket member carried onthe end of the shank, said socket member including a forwardly facingupstanding face, a pair of generally parallel shoulders extendingforwardly beyond said face, a frusto-conical socket opening formed insaid socket member and extending rearwardly of said face, a digger toothcarried by said socket member, a frusto-conical plug formed at the rearof the tooth and having a size and shape comparable to that of thesocket opening for cooperative engagement with the wall surface of saidopening to transmit horizontal and vertical thrust thereto, means fordrawing said plug into said socket opening and for retaining said plugtightly in said opening, said tooth further including a digging portionformed at the forward end thereof and subject to receiving twistingthrusts tending to rotate the tooth about the axis of said plug, saiddigging portion including References Cited by the Examiner UNITED STATESPATENTS 1,395,048 10/21 McKee 37-142 1,540,314 6/25 Clark 37l412,847,921 8/58 Heckathorn 172-699 2,919,506 1/60 Larsen 37142 ReferencesCited by the Applicant UNITED STATES PATENTS 2,385,395 9/45 Baer.

SAMUEL KOREN, Primary Examiner.

25 A. JOSEPH GOLDBERG, LUCIE H. LAUDENSLA- GER. Examiners.

